Spark Plug Upgrades

Spark Plug Upgrades

The N54 and N55 platforms are being pushed with unbelievable success these days. However, when you are adding boost and pushing the motor farther than the engineers designed it can cause problems. The worst case is knock from pre-ignition. This is when the fuel and air mixture ignites from heat before the piston is at Top Dead Center. This can cause catastrophic motor failure. 

Have no fear though. getting around this issue is easy! Installing upgraded plugs reduced the temperature so pre-ignition, aka "knock", cant occur. 


  • Our Stage 1 plugs are one step colder than factory. This is good for engines seeing  higher than stock horsepower, full-bolt-on upgrades. The plug gap must be manually set using a gap tool to the suggested 0.022". The tighter gap and exposed electrode design typically results in fewer misfires at higher power levels than the stock plugs. 


  • Our Stage 2 plugs are two steps colder than factory. suggested for higher boost E85, water/meth injection, and/or upgraded turbochargers. We suggest setting the gap down to 0.020".

These plugs are suggested for most turbo BMW motors including the N20, N54, N55, S55, N63, N63TU, S63, and S63TU applications.

Beware of counterfeit NGK plugs being sold for $5-10 each on eBay and Amazon. They do not offer the same performance, lifespan, and knock resistance. NGK plugs from SLG are guaranteed authentic.